This  is a fermentation associated process. Chillies are added to various carbohydrate substrates, (Rice powder and barley sprout malt) and inoculated with a mould with the Meju powder. The fermentation is allowed to proceed for a month in the warm (sun). Presumably salt is added to inhibit rogue cultures of bacteria into the mix. 

Ingredients:
  • 7 1/2 cup Glutinous rice powder
  • 5 1/2 cup Chili powder
  • 5 1/2 cup Salt
  • 4 cup Yeodkireum powder - (dried barley sprout malt)
  • 2 cup Meju powder (soy bean with Aspergillus oryzae mould inoculum)*
  • 8 1/3 cup Water
Method:
  1. In a bowl, combine Yeodkireum powder and water. Mix well, then strain off liquid into a large pot.
  2. Add glutinous rice powder to liquid and mix well. Cook over low heat (113F, 45C). Remove from heat and allow to stand until rice powder is dissolved.
  3. Heat to boiling, then reduce heat and let cook for 30 minutes. Transfer to a large bowl to cool.
  4. When completely cool, stir in Meju and chili powder and blend well. Leave overnight.
  5. The next day, mix in 4 cups of the salt and transfer mixture to a large container. Sprinkle remaining salt over, then cover with loosely woven cloth such as cheesecloth or gauze. Leave in a sunny place to ferment, stirring occasionally, for one month.

ADDITIONAL NOTES: Use a large container, as mixture rises as it ferments. During fermentation, cover container at night.

Korean 'Meju powder' is made by inoculating cooked soya beans with Aspergillus sp. mould and then drying and crushing. It appears to be the same as Japanese Kome-koji, and therefore is another source of enzyme producing moulds to make a rice mash/wine.
http://www.koreansauce.com/Eng/eco/sec03.htm
http://www.ichief.com/recipe.cfm Search - Kochu Jang (Hot Sauce)

Korean 'Yeodikireum powder' appears to be the same as European crushed malted barley (i.e. sprouted).